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Are these 4th gens with lt1 typically requiring a restrictor?
If so where can I find such a thing?
Signed
Confused and scared Ford guy

Several of the guys have gone to exhaust restrictors.
On the cars that I wrench on, I hated how much oil got
trapped up around the throttlebody because of the wierd
air flow around the restrictor plate. Sean (#15), Paul (#88)
and David (#39) have all converted over to tail pipe
restrictors. They aren't hard to install or tune.

6.21.4 All Cars may install a restrictor between the air filter and intake manifold to reduce horsepower and torque. The diameter and thickness of the restrictor plate orifice(s) shall be noted on the Dyno Sheet and must match at all times. Carbureted cars may install a mechanical throttle stop on the carburetor linkage for the same purpose. Throttle stop dimensions must be noted on the Dyno Sheet for inspection purposes and must match at all times.

6.24.3 Any suitable exhaust system may be used after the manifolds (or headers on cars that are allowed headers). The exhaust must exit behind the driver and be directed away from the car. Mufflers may be required to meet sound regulations depending on track location.

Was/is there a reason that an exhaust restrictor is not specifically mentioned in the rules?

6.24.3 Any suitable exhaust system may be used after the manifolds (or headers on cars that are
allowed headers). The exhaust must exit behind the driver and be directed away from the car.
Mufflers may be required to meet sound regulations depending on track location.

It's in there...

As I understand the intent of HP/TQ rule, one would declare (as I do) that there is an exhaust restrictor. Certainly I can change that but gain the risk of being non compliant, and non compliant on purpose gets too close to trying to circumvent the rule, or cheat, if you will.

I think I'll add that to my RCR list this year. Make it more clear that exhaust restrictors are allowed as they seem to fall within the intent of the series. How easy are they to police? We'd need to update the dyno sheet too so it has a more definitive home.